Air spaces and air gaps in an explosives column are known to allow greater distribution and cushioning of explosive energy from the rock mass. This energy distribution is enhanced if the explosives' gases can be confined in the borehole for as long as possible by plugging and stemming above the air space.Power Plug is an inflatable plug which can seal a borehole at any point to separate the stemming from an air gap and explosive toe load.

The location of Quintette Coal Limited's pit and geologic nature of the dedicated reserves combine to introduce a number of factors which can adversely affect waste dump stability. These factors include steep terrain, variable material type and particle size, and precipitation. This paper describes the solutions to related waste dump problems. A brief geotechnical review of the waste dumps is given and Quintette's operational strategies during periods of dump stability and instability are...

The six mineable coal seams at Quintette Coal Limited (QCL) vary in thickness from 0.75 m to 9.5 m and include waste partings varying from 0.2 m to 4 m thick. They are highly faulted and folded in some areas and dip angles range from horizontal to 90 degrees. Due to this variation in thickness and orientation of the seams, several different mining methods are used to economically recover the coal. The key to QCL's success depends on the timely collection of detailed geology data and on mine...

A diversity of structures and rock types in the Afton pit has resulted in the occurrence of several different types of wall failure. Delivery of ore to the mill has not been affected and safety has not been compromised thanks to effective remedial work and to a system of structural mapping, back analyses of failures, groundwater monitoring, and simple movement monitoring. Remedial measures have included artificial support, dewatering (including vacuum-assisted drainage), flattening of slopes...

This paper describes the investigation of a large, progressive slope failure on the southeast wall of the east pit at Highmont Mine, British Columbia Geotechnical investigations consisted of geological and structural mapping, assessment ofblasthole drilling records, review of rock core information, slope movement monitoring and back analysis of various possible failure modes. Climate records and mining history were also assessed to determine their relationship to slope movement.Analysis of...

Future open pit metallurgical coal mines in western Canada will be developed in complex geological environments. The success of these operations will be influenced by the mine operators' ability to prepare accurate mine plans and to predict and, subsequently, to control both out-of-seam dilution and coal recovery. Quintette Coal Limited has been mining its tightly folded and severely faulted Mesa deposit at annual rates of up to 9 Mt of raw coal, since October 1982. Ongoing development...

The Suncor Oil Sands Mine located north of Fort McMurray, Alberta, produces about 80 000 m3 per day of tailings waste which must be disposed of economically in an environmentally acceptable manner. To date, this has been accomplished by impounding the high water content tailings wastes behind large dykes, many of which approach 100 m in height.The dykes are constructed using suitable overburden material stripped prior to the mining of the oil sands feed and/or the coarse sandy fraction of...